"I have had a good example this year of the role of leaf area in
ripening fruit."

"I removed some lower leaves just before netting a few days ago
to help ripening."

I think you had the right idea in the first comment. Pulling leaves
doesn't help ripening. In fact, it will delay it. The vine takes time
to readjust it's physiology to compensate for the lost leaves. In an
environment like yours you need all the leaves you can get. People who
grow grapes in California or an area with more sunshine and heat have
much more room to hack up the vines, you don't.

"

On Aug 28, 8:36*am, michael > wrote:
> I received some very interesting advice a month or two ago,concerning
> the thinning of vertical shoots for grapes trained in the Double Guyot
> method.I pruned the sidehoots to one or two leaves earlier when the
> canopy was in full growth,and since the beginning of August have left
> more on.I removed some lower leaves just before netting a few days ago
> to help ripening.
> I have an excellent crop this year,which seems to be ripening well.My
> mini vineyard is in Herefordshire,England,and we have to be satisfied
> with Brix values maximising at about 18 for reds or whites.However one
> of my reds is already at 14.0,a couple of weeks before harvest,which
> will be early this year in England.Our temperatures have not been
> great in the daytime at 20-22C,but the night time temperatures have
> not fallen below 15C.I live about 120 miles from my vines,so have to
> make a judgement when to visit.The average temperature (24hr average)
> at present is about 15C,and I am wondering if anyone uses a rule of
> thumb to estimate the increase in Brix/day for a given average(24hr)
> temperature.
>
> I have had a good example this year of the role of leaf area in
> ripening fruit.We have a large damson tree in our garden,which
> produces a good crop of sweet damsons each year.This year there has
> been an enormous crop (twice or three times normal),and they have all
> fallen now,but with none of them ripe.I assume that this is the same
> with vines.The balance of leaf to fruit is crucial,and with a large
> crop,it is important to maintain a maximum leaf area,consistent with
> keeping protection against powdery mildew-good air flow and spray
> coverage.
>
> I have also for the first time put on a three inch layer of garden
> compost around each vine in the early spring period.I had not done
> this previously,since I thought the vines were vigorous enough in our
> cool climate.However,although the vigour has increased somewhat
> further,the vines look incredibly healthy,with little powdery mildew,
> and I had a very good flower set.I think the compost keeps the soil
> more moist,thus avoiding a major powdery mildew attack in very dry
> spells.
>
> Michael